The economics of powder coating easily beat other MDF finishing methods. Consider a production line which is running at 14 feet/min (4.3 m/min). The number of kitchen cabinet doors produced each minute (average size of 30 inches by 14 inches [2.9 square feet]).
At this rate of production with an average combined primer and topcoat thickness of 4.0 to 5.0 mils, the powder usage is 120 pounds an hour. This will produce a material cost in the range of $0.12 to $0.15 per square foot. Most components will require a finish on both sides, yielding a total cost of $0.24 to $0.30 a square foot of finished MDF.
Foil Wrapped MDF more than four times as expensive to Produce
Comparing the cost to vinyl or foil (PVC) wrap MDF, powder is very competitive. PVC has a yield after wastage due to trimming of $0.60 to $0.80 a square foot, plus $0.10 for the glue line and $0.18 for the melamine-backed MDF, which totals almost $1.10 a square foot. The labor content of a powder coated door is substantially less than that for a wrapped door, while powder coating offers an uninterrupted flow through process completing the coating in a load to unload time of approximately 45 minutes.
Powder Coated MDF for Toughness
An MDF part that has been powder coated is significantly tougher in use than either a foil wrapped part or a liquid finished part, thus offering a better quality product at less cost. The latest powder technology that is coming to market, enables either single or two coat processes that can now be used in high humidity areas such as bathrooms, and can be cured in less than 5 minutes at 130°C.
Gas Catalytic Infrared v. Electric Infrared v. Convection Oven
The use of powder coating infrared ovens as opposed to convection ovens for the pre heat and cure cycles is the most cost effective method to cause the MDF to become conductive and to cure the powder without removing the water content from the MDF board. Catalytic infrared is more effective over electric infrared in as much as the IR leaving the catalyst surface is multi directional and emerges from a cloud of water vapor and carbon dioxide which are bi products of the catalytic chemical reaction. These hot gases provide a low intensity long wave infrared that is more easily absorbed by the powder on the surface of the MDF, raising the surface temperature quickly and uniformly through out the thickness of the powder.
An additional benefit of powder coating is the absence of a parting line between the melamine and PVC. The powder completely encapsulates the MDF. Being able to produce large quantities of finished parts without human interference is another big plus for powder.
Economics of Powder Coating MDF Proven
It is clear that the argument has been proven. A powder coated MDF part, cured in a gas catalytic infrared oven is cheaper to produce than any other finish. and tougher in use. Heraeus Vulcan has been at the fore front of the latest developments in oven cure technology and PLC controls to ensure the optimum cure.